This report describes the quality improvement efforts of early childhood education programs participating in Iowa's Quality Rating System (QRS). It identifies supports and barriers to quality improvement and examines how quality improvement supports and activities relate to changes in program quality ratings across time. The study team developed the following research questions for this study in partnership with stakeholders in Iowa. Among early childhood education programs participating in the Iowa QRS: (1) What are the quality improvement activities in which they participate; (2) What topics are covered in professional development; (3) What are the supports and barriers to participation in quality improvement activities; (4) What information do they use to make decisions about quality improvement activities: (5) Do ratings rise among programs that renew their Iowa QRS participation; and (6) What is the relationship between quality improvement supports and activities and increases in QRS ratings and domain scores? The descriptive findings of this study provide an overview of the landscape of quality improvement activities among early childhood education programs participating in the Iowa QRS. The results suggest that in-person training is the most common type of quality improvement activity in Iowa, perhaps partly because annual in-person training hours are required to maintain home provider registration or center licensing. While staff in almost all programs completed in-person training, staff in approximately half the programs participated in web-based training. However, many survey respondents identified long distance and travel time as barriers to participation in quality improvement activities such as training. Appended are: (1) Supplemental literature review; (2) Iowa Quality Rating System rating criteria; (3) Data and methodology; (4) Quality improvement survey items; and (5) Detailed results tables.